Mingling of genes four millennia ago suggests continent was not isolated after all.

Some aboriginal Australians can trace as much as 11% of their genomes to migrants who reached the island around 4,000 years ago from India, a study suggests. Along with their genes, the migrants brought different tool-making techniques and the ancestors of the dingo, researchers say1.

This scenario is the result of a large genetic analysis outlined today in the Proceedings of the National Academy of Sciences1. It contradicts a commonly held view that Australia had no contact with the rest of the world between the arrival of the first humans around 45,000 years ago and the coming of Europeans in the eighteenth century.

Australia is thought to represent one of the earliest migrations for humans after they left Africa, but it seemed pretty isolated after that, says Mark Stoneking, a geneticist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who led the study.

Irina Pugach, a postdoctoral researcher in Stonekings laboratory, discovered signs of the Indian migration by comparing genetic variation across the entire genomes of 344 individuals, including aboriginal Australians from the Northern Territory, highlanders from Papua New Guinea, several populations from Southeast Asian and India and a handful of people from the United States and China.

Pugach confirmed an ancient association between the genomes of Australians, New Guineans and the Mamanwa  a Negrito group from the Philippines. These populations diverged around 36,000 years ago, suggesting that they all descended from an early southward migration out of Africa.

It was an easy travel distance for an experienced ocean-going canoe culture.

Sri Lanka is just off the coast of southern India. Then it is only about 600 miles east to the southern archipelogo of Malaysia and Indonesia. And that is only if you didn't want to start out by land from northeast India, trek across to Burma, down into Thailand and south into Malaysia and then across to Indonesia. Though, I expect a mostly land route might have (a) taken longer, (b) met more people already settled along the way and (c) experienced more migrants settling, or being killed somewhere before they ever got down to Indonesia and Australia.

It is even less difficult after crossing the ocean from Sri Lanka to just island hop down the archipelogo of southern Malaysia and Indonesia until you are hopping along very southern Indonesia and in the Timor Sea. That leaves a route of less than 250 miles south across to northern Australia. Don't ask if they just got across from Indonesia to Australia by accident - taken that way by oceans currents??? - or if someone had once made it back to them from such an accident and informed them of a big land in the "southern sea", and remembered how to get there. Who knows??/p>

Given what I see as the ease of it, there must have been a lot to the living context in that part of Asia that made such travels/migrations less frequent than they seem to have been - or maybe a great many of such travellers either did NOT survive the journey or did not survive in equal numbers in barren northern Australia. We can only wonder.

It just seems that the journey was not extremely difficult, but an 11% contribution to what is itself a small gene pool suggests there was either, for whatever reason, not a whole lot who undertook the journey, or not whole lot who had great success in it.

I am sure many prognosticating cultural anthropologists are about to tell us they know why the migrations from the Indian subcontinent to Australian were as small as they seem to have been. I never accept their guesses. I have no problem leaving unanswerable questions unanswered.

No. For what it’s worth, NOVA just had a show last week that confirmed that most populations, except sub Saharan africans, have Neanderthal genes. Europeans apparently have the most. It is thought that these Neanderthal genes help confer immunity to many diseases.

July 18, 2011  Some of the human X chromosome originates from Neanderthals and is found exclusively in people outside Africa, according to an international team of researchers led by Damian Labuda of the Department of Pediatrics at the University of Montreal and the CHU Sainte-Justine Research Center. The research was published in the July issue of Molecular Biology and Evolution

No, I haven't read either. I merely posted them because I think they relate to ancient sea travels from a pacific asian culture. I'm not sure if the detail is related to DNA, but probably more so Archeology finds and influence.

Sea travel dates back forever, and I'm never surprised where castaways and sea drift end up.

the only thing that resonates with me from the thesis (which he borrowed) by the Philippino-American author is his premise that migrations from mainland Asia and/or it’s nearby islands to points east and south were neither one-off events or one directional

that I have always believed

and though that author cannot and does establish real proof of it, nor can I, it makes more sense

than believing that no matter how some persons migrated or how far that migration was, that no one ever wanted and no one ever managed to return back to where they had migbrated from, and that others did not learn about how to do that, and over time some of the migration did not go forth and some back as well, and some in new directions and from new places to older new places - forming known trade and migration routes over long expanses of time

the idea makes “human sense” to me

the human mind has not grown in thousands of years; the genetic wiring for the brain’s nueral net has been there a long time; humans have always been smart, inventive, creative, curious, determined and willing to change

it may have taken us a very long time to develop our tools from pre-stone age to now, but we have always been very smart at using the tools we did knew about, and even long long ago we did some amazing things with them too

“trade networks” across vast land and ocean expanses??

sounds to me like something any of age of man would accomplish in some way

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